基于GNSS的农田平整定位精度优化与试验

基于全球卫星导航系统（Global navigation satellite system, GNSS）农田平整作业中，GNSS定位数据不仅是地形测量和基准面设计的基础，而且在平地作业中实时影响农田平整的精度。针对当前GNSS定位数据误差分析较少，提出一种基于联合滤波算法的GNSS定位数据分析处理方法。分析平地作业过程中GNSS定位数据的误差源，结合多路径效应和随机噪声，提出因地形起伏引起的振动误差校正方法，利用卡尔曼、小波变换联合滤波算法，校正数据误差提高定位精度，农田定位对比试验分析表明，高程定位精度明显提高，平地工作中，GNSS定位实际高度波动范围缩小20%，能够更好的指导农田平整工作。

Optimization and Analysis of Location Accuracy Based on GNSS-controlled Precise Land Leveling System

During the work of GNSS (Global navigation satellite system) controlled land leveling system, the GNSS location data is not only the basis of topographic survey and land leveling datum design, but also affects the accuracy of land leveling in real time. In the land leveling work, if the GNSS location data is not accurate enough, the results of the terrain measurement can not truly reflect the actual terrain data and affect the entire farmland land leveling process. In order to analyze the GNSS location data error and improve the location accuracy, we proposed a method to analyze the error source of GNSS location data in the process of land leveling work. Combining the multi-path effect and random noise in the process of GNSS location data, we proposed an error correction method of vibration error caused by terrain fluctuation in land leveling work. We use the Kalman filter algorithm and Wavelet transform to process the location date and correct the data error, we can improve the positioning accuracy. We do farmland comparison experiments, and the analysis results showed that, in this method, the height location accuracy increased, during the land leveling work the GNSS positioning actual height fluctuation error range reduced by 20%, so we can use the method to guide land leveling work better, and can give the follow-up research scientific and rational positioning data, provide reliable data support.